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Acta Pharmaceutica Sinica B 2024年第5期14卷 2349-2357页

作者： Rabea Voget Julian Breidenbach Tobias Claff Alexandra Hingst Katharina Sylvester Christian Steinebach Lan Phuong Vu Renato H.Weiße Ulrike Bartz Norbert Sträter Christa e.Müller michael Gütschow Pharmaceutical Institute Pharmaceutical&Medicinal ChemistryUniversity of BonnBonn 53121Germany Institute of Bioanalytical Chemistry Center for Biotechnology and BiomedicineLeipzig UniversityLeipzig 04103Germany Department of Natural Sciences University of Applied Sciences Bonn-Rhein-SiegRheinbach 53359Germany

A titrant for the SARS-CoV-2 main protease(M^(pro))was developed that enables,for the first time,the exact determination of the concentration of the enzymatically active M^(pro) by active-site *** covalent binding mode of the tetrapeptidic titrant was elucidated by the determination of the crystal structure of the enzyme–titrant *** fluorogenic substrates of M^(pro),including a prototypical,internally quenched Dabcyl-eDANS peptide,were compared in terms of solubility under typical assay *** exploiting the new titrant,key kinetic parameters for the M^(pro)-catalyzed cleavage of these substrates were determined.

关键词： COVID-19 SARS-CoV-2 Main protease Peptide nitriles Fluorogenic substrates Active-site titration X-ray crystallography Inner filter effect

Diabetes and pulmonary infection:how hyperglycaemia shapes the immune system

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1245-1246页

作者： Christian Herder michael Roden Nicolas Venteclef Institute for Clinical Diabetology German Diabetes CenterLeibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf40225DüsseldorfGermany German Center for Diabetes Research(DZD) Partner Düsseldorf85764München-NeuherbergGermany Department of endocrinology and Diabetology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University Düsseldorf40225DüsseldorfGermany Institut Necker-enfants Malades(INeM) UniversitéParis CitéINSERM UMR-S1151CNRS UMR-S8253ParisFrance

In a recent study published in Nature,Nobs and colleagues aimed to identify novel mechanisms that may explain why diabetes is associated with an increased susceptibility to viral respiratory *** analyses revealed a central role of lung dendritic cells(DC)which exhibited several functional defects induced by hyperglycaemia and consequently result in impaired antiviral immune responses.

关键词： impaired lung respiratory

Iterative Subregion Correction Preconditioners with Adaptive Tolerance for Problems with Geometrically Localized Stiffness

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Communications on Applied Mathematics and Computation 2024年第2期6卷 811-836页

作者： michael Franco Per-Olof Persson Will Pazner Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720-3840USA Fariborz Maseeh Department of Mathematics and Statistics Portland State UniversityPortlandOR 97201USA

We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated *** preconditioners are designed to treat the case of geometrically localized stiffness,where the convergence rates of iterative methods are degraded in a localized subregion of the *** convergence may be caused by a number of factors,including the mesh size,anisotropy,highly variable coefficients,and more challenging *** approach taken in this work is to correct well-known preconditioners such as the block Jacobi and the block incomplete LU(ILU)with an adaptive inner subregion *** goal of these preconditioners is to reduce the number of costly global iterations by accelerating the convergence in the stiff region by iterating on the less expensive reduced *** tolerance for the inner iteration is adaptively chosen to minimize subregion-local work while guaranteeing global convergence *** present analysis showing that the convergence of these preconditioners,even when combined with an adaptively selected tolerance,is independent of discretization parameters(e.g.,the mesh size and diffusion coefficient)in the *** demonstrate significant performance improvements over black-box preconditioners when applied to several model convection-diffusion ***,we present performance results of several variations of iterative subregion correction preconditioners applied to the Reynolds number 2.25×10^(6)fluid flow over the NACA 0012 airfoil,as well as massively separated flow at 30°angle of attack.

关键词： Subregion correction Nested Krylov Geometrically localized stiffness

Water quality, habitat, and fish assemblage relationships in middle-order agriculture and forest streams of the Mississippi Alluvial Plain

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ecological Processes 2024年第01期13卷 217-236页

作者： Matthew L.Skoog michael A.eggleton Yushun Chen Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Minnesota Department of Natural Resources State Key Laboratory of Freshwater ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences

Background Agriculture has greatly influenced water quality, habitats, and fish assemblages in streams of the Mississippi Alluvial Plain(MAP) ecoregion. However, MAP streams have historically been understudied compared to streams in other agricultural regions of the USA. In this study, water quality, habitat, and fish assemblage composition were assessed seasonally(spring, summer, and fall) in eight representative MAP streams located across three U.S. states. The study design included four streams containing highly agricultural watersheds(herein termed “agriculture” streams) and four streams containing mostly forested watersheds(herein termed “forest” streams), which were intended to represent reference conditions for MAP *** In general, forest streams contained significantly better instream and riparian habitats than agriculture streams(P = 0.010–0.040) whereas agriculture streams contained significantly greater levels of primary nutrients(P erences between agriculture and forest streams with respect to other physical and chemical variables were intermittent and season dependent. Fish assemblages in agriculture and forest streams were structured primarily along an environmental gradient reflecting instream habitat conditions, water nutrient concentrations, and benthic chlorophyll-a production. Structurally, fish assemblages in both stream types contained many regionally common species, though some species appeared to exhibit affinities for a particular stream type. Functionally, fish assemblages in agriculture streams contained more tolerant species, more omnivores, and fewer insectivores compared to forest stream assemblages, which were nearly all insectivores. Overall, one-third of the fish specimens collected in forest streams classified as intolerant *** Our results suggested that stream water quality, habitat, and fish assemblages differed between agriculture and forest streams in the MAP, with fish assemblages e

关键词： Agriculture Stream Land use Water quality Habitat Fish Multivariate statistics Mississippi Alluvial Plain

Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: emphasis on fowl and swine

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动物营养学报 2024年第1期16卷 422-428页

作者： edwin T. Moran michael R. Bedford Poultry Science Department Auburn University AL 36830-5416 USA AB Vista Woodstock Court Blenheim Road Marlborough Wiltshire SN8 4AN UK

Phytin is the Ca 2+ -Mg 2+ -K + salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca 2+ . even at low gastric pH, phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca 2+ near the enzyme's active site further stabilizes its newly formed structure. Thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide's basic amino acids; coordinating free Ca 2+ , destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca 2+ and other cations re-bind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes (e.g. Ca 2+ , Zn 2+ ) which reduces their structural resistance to autolysis and ability as co-factors (e.g. Zn 2+ ) to increase enzyme activity. Goblet cells initially employ Ca 2+ as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca 2+ is progressively displaced by Na + to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer (USWL). excessive removal of Ca 2+ from mucin by phytic acid increases its fluidity facilit

关键词： Digestive enzyme Calcium endogenous protein Mucin Phytin

Developing a multi-method approach to identifying e-scooter hazard hotspots

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Journal of Traffic and Transportation engineering(english edition) 2024年第4期11卷 667-680页

作者： michael Hardinghaus Simon Nieland Rebekka Oostendorp Jan Weschke German Aerospace Center(DLR)Institute of Transport Research Berlin 12489Germany

In recent years,e-scooters have been introduced in many european *** several places we have witnessed a rapid uptake of this new mode of transport mainly as a result of public sharing schemes.A number of incidents,injuries and even fatalities have given rise to questions regarding the safety of these *** questions are being researched mainly using official crash data and data specifying injuries and hospital *** now,the research has focused on investigating typical injury patterns and estimating risk *** little is known about exactly where conflicts and crashes *** of hazard hotspots is crucial when investigating risk levels and improving safety for all road ***,this paper develops an approach to investigating locations with potentially dangerous interactions within the active mobility system in the city of *** approach consists of explorative expert interviews,an online poll,and quantitative *** the latter we combine three ***,we research crash hotspots using official ***,we use data based on acceleration sensors from cyclists'smartphones to find locations of sudden ***,we use trip data from the operators of escooter sharing *** information gathered is used in a conclusive expert workshop to identify hazard *** show that many of the conflicts with pedestrians are caused by parked ***,e-scooter trips are concentrated in the inner city and along specific *** moving traffic,various data sources are used to identify hotspots at intersections and in areas between *** present research lays the foundation for important further studies to investigate interactions at hotspots in detail by determining nine specific locations in the city of Berlin.

关键词： e-scooter Accidents Crashes Active mobility Micromobility Road safety

Anisotropic time-dependent behaviors of shale under direct shearing and associated empirical creep models

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Journal of Rock Mechanics and Geotechnical engineering 2024年第4期16卷 1262-1279页

作者： Yachen Xie michael Z.Hou Hejuan Liu Cunbao Li Shenzhen Key Laboratory of Deep engineering Sciences and Green energy Shenzhen UniversityShenzhen518060China Institute of Subsurface energy Systems Clausthal University of TechnologyClausthal-Zellerfeld38678Germany State Key Laboratory of Geomechanics and Geotechnical engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

Understanding the anisotropic creep behaviors of shale under direct shearing is a challenging *** this context,we conducted shear-creep and steady-creep tests on shale with five bedding orientations (i.e.0°,30°,45°,60°,and 90°),under multiple levels of direct shearing for the first *** results show that the anisotropic creep of shale exhibits a significant stress-dependent *** a low shear stress,the creep compliance of shale increases linearly with the logarithm of time at all bedding orientations,and the increase depends on the bedding orientation and creep *** high shear stress conditions,the creep compliance of shale is minimal when the bedding orientation is 0°,and the steady-creep rate of shale increases significantly with increasing bedding orientations of 30°,45°,60°,and 90°.The stress-strain values corresponding to the inception of the accelerated creep stage show an increasing and then decreasing trend with the bedding orientation.A semilogarithmic model that could reflect the stress dependence of the steady-creep rate while considering the hardening and damage process is *** model minimizes the deviation of the calculated steady-state creep rate from the observed value and reveals the behavior of the bedding orientation's influence on the steady-creep *** applicability of the five classical empirical creep models is quantitatively *** shows that the logarithmic model can well explain the experimental creep strain and creep rate,and it can accurately predict long-term shear creep *** on an improved logarithmic model,the variations in creep parameters with shear stress and bedding orientations are *** abovementioned findings,a mathematical method for constructing an anisotropic shear creep model of shale is proposed,which can characterize the nonlinear dependence of the anisotropic shear creep behavior of shale on the bedding orientation.

关键词： Rock anisotropy Direct shear creep Creep compliance Steady-creep rate empirical model Creep constitutive model

Spontaneous mutations and mutational responses to penicillin treatment in the bacterial pathogen Streptococcus pneumoniae D39

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Marine Life Science & Technology 2024年第3期6卷 198-211页

作者： Wanyue Jiang Tongtong Lin Jiao Pan Caitlyn eRivera Clayton Tincher Yaohai Wang Yu Zhang Xiang Gao Yan Wang Ho‑Ching T.Tsui Malcolm e.Winkler michael Lynch Hongan Long Institute of evolution and Marine Biodiversity KLMMEOcean University of ChinaQingdao 266003China Laboratory for Marine Biology and Biotechnology Laoshan LaboratoryQingdao 266237China Department of Biology Indiana UniversityBloomingtonIN 47405USA School of Mathematics Science Ocean University of ChinaQingdao 266000China State Key Laboratory of Microbial Technology Microbial Technology InstituteSchool of Life ScienceShandong UniversityQingdao 266237China Biodesign Center for Mechanisms of evolution Arizona State UniversityTempeAZ 85281USA

Bacteria with functional DNA repair systems are expected to have low mutation rates due to strong natural selection for genomic ***,our study of the wild-type Streptococcus pneumoniae D39,a pathogen responsible for many common diseases,revealed a high spontaneous mutation rate of 0.02 per genome per cell division in mutation-accumulation(MA)*** rate is orders of magnitude higher than that of other non-mutator bacteria and is characterized by a high mutation bias in the A/T *** high mutation rate may have resulted from a reduction in the overall efficiency of selection,conferred by the tiny effective population size in *** line with this,*** D39 also exhibited the lowest DNA mismatch-repair(MMR)efficiency among *** with the antibiotic penicillin did not elevate the mutation rate,as penicillin did not induce DNA damage and *** lacks a stress response *** findings suggested that the MA results are applicable to within-host scenarios and provide insights into pathogen evolution.

关键词： Neutral evolution Mutation spectrum Antibiotics DNA mismatch repair Oxidative damage repair

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海洋工程力学及应用

国外科技新书评介 2016年第8期 15-15页

作者： michael e. mccormick 谈庆明不详中国科学院力学研究所

本书为固定和浮动结构提供水波和波与结构相互作用的导论。书中介绍了水波力学基础，包括对线性和非线性规则波的完整讨论，作者还提出了决定随机波的平均性质的方法。随后，作者阐述了海洋工程力学在海岸工程方面的应用。

关键词：工程力学应用海洋结构相互作用浮动结构力学基础海岸工程非线性

New perspectives on biology,disease progression,and therapy response of head and neck cancer gained from single cell RNA sequencing and spatial transcriptomics

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Oncology Research 2024年第1期32卷 1-17页

作者： GeRWIN HeLLeR THORSTeN FUeReDeR ALeXANDeR michael GRANDITS ROTRAUD WIeSeR Division of Oncology Department of Medicine IMedical University of ViennaVienna1090Austria Ludwig Boltzmann Institute for Hematology and Oncology Medical University of ViennaVienna1090Austria

Head and neck squamous cell carcinoma(HNSCC)is one of the most frequent cancers *** main risk factors are consumption of tobacco products and alcohol,as well as infection with human papilloma *** therapeutic options comprise surgery,radiation,chemotherapy,targeted therapy through epidermal growth factor receptor inhibition,and immunotherapy,but outcome has remained unsatisfactory due to recurrence rates of~50%and the frequent occurrence of second *** availability of the human genome sequence at the beginning of the millennium heralded the omics era,in which rapid technological progress has advanced our knowledge of the molecular biology of malignant diseases,including HNSCC,at an unprecedented ***,microarray-based methods,followed by approaches based on next-generation sequencing,were applied to study the genetics,epigenetics,and gene expression patterns of bulk *** recently,the advent of single-cell RNA sequencing(scRNAseq)and spatial transcriptomics methods has facilitated the investigation of the heterogeneity between and within different cell populations in the tumor microenvironment(e.g.,cancer cells,fibroblasts,immune cells,endothelial cells),led to the discovery of novel cell types,and advanced the discovery of cell-cell communication within *** review provides an overview of scRNAseq,spatial transcriptomics,and the associated bioinformatics methods,and summarizes how their application has promoted our understanding of the emergence,composition,progression,and therapy responsiveness of,and intercellular signaling within,HNSCC.

关键词： Head and neck squamous cell carcinoma Tumor microenvironment Immunotherapy Gene expression Omics